Jeff Marion conducts research on visitor impacts and sustainable recreation management for the National Park Service and other protected natural areas (https://www.usgs.gov/staff-profiles/jeff-marion). An avid outdoor recreationist who enjoys backpacking, climbing, caving, and canoeing, he has served as a Scoutmaster and co-ed Venture Crew Leader for more than 22 years. He has authored more than 170 scientific publications and routinely consults with park and recreation managers to improve the sustainability of recreation visitation to avoid or minimize resource and social impacts. A founding member of the national Leave No Trace program’s board of directors, he chaired its Educational Review Committee for a decade, helping to develop and refine a diverse array of low impact principles and practices.